Evaluating the linguistic evidence for an Out of America hypothesis

June 11, 2008

A lively debate has been going on over at anthropology.net regarding a proposal by German Dziebel, expounded in his recent book, that modern humans originated in the Americas and spread from there to the rest of the world — an Out of America (OOAm) hypothesis to mirror the more widely-accepted Out of Africa (OOAf) hypothesis. The debate has been stimulated by two posts by Dziebel (here and here), which argue that many diverse sources of data suggest that modern humans originated in the Americas, or at the very least, the available data certainly do not rule this possibility out. Much of the debate in the comment threads focuses on genetic arguments, as one might expect, but I was interested in the linguist evidence. I asked Dziebel to elaborate on the linguistic evidence, and he kindly responded as follows:

Regarding the relevance of linguistic diversity in the Americas to the problem of the peopling of the Americas, I base myself off of Johanna Nichols’s “Linguistic diversity and the first settlement of the New World.” Language 66:3. (1990) as well as her Linguistic Diversity in Space and Time (1992).

Being stranded in Lima as I am, I have no access to Nichols’ 1992 book, but I was able get the Language article through JSTOR. In this post my goal is basically to evaluate to what degree the evidence and arguments presented in Nichols (1990), cited by Dziebel in support of the OOAm hypothesis, in fact support this hypothesis. For those who want the Reader’s Digest summary, my conclusions are the following: to a large degree, the basic evidence given in Nichols (1990) is neutral with respect to the OOAm hypothesis or competing hypotheses that place human origins in other continents. However, those parts of the paper that raise arguments relevant to distinguishing various origin hypotheses come down in favor of America as a site of colonization from the Old World, and not as a site from which humans migrated. (Just to be clear: I am not arguing for or against the OOAm hypothesis as a whole, but rather, taking on the much more restricted question of whether the linguistic evidence that Dziebel cites in fact supports the OOAm hypothesis.)

For Dziebel, the interesting point of Nichols (1990) lies in the relatively high linguistic diversity of the Americas and the implications of this diversity for the antiquity of human presence in the Americas. In his comment to me, Dziebel writes:

As measured by the number of independent linguistic stocks, linguistic divergence in the Americas must have taken at least 35,000 years. Of course, this figure cannot be taken literally but there’s a marked contrast between language diversity in the Americas (and in places like Papua New Guinea, with human archaeological record of some 40,000 years) and language diversity in Africa.

Dziebel raises two points here that are based on Nichols (1990). First, the linguistic diversity found in the Americas suggests that the human presence in the Americas goes back at least 35,000 years. And second, the human diversity of the Americas is significantly greater that found in Africa.

The arguments that Nichols (1990) marshals for the early date for the initiation of human migration to the Americas are very interesting, and rely on converging sources of data. However, the single most important piece of evidence is the sheer number of linguistic stocks found in the Americas. If we follow a uniformitarian assumption about rates of linguistic differentiation, and then calculate the rate of development of distinct stocks in other parts of the world, we are led to the conclusion that there is simply no way that the linguistic diversity we find in the Americas could have developed in the time window given by Clovis-based chronologies that posit that colonization of the Americas began around 12,000 years ago, or more recent accepted chronologies that push that date back to about 20,000 years ago. Pulling together as much linguistic and and archeological evidence as she can about migration rates across Beringia and the Bering Straits, Nichols suggests a date of roughly 35,000 years for the initial migrations into the Americas.

If we abstract away from the colonization-based scenario that Nichols employs, as Dziebel clearly does, we could argue that Nichols calculations support human presence in the Americas from 35,000 years ago — whether due to migration or otherwise. However, this interesting result cannot distinguish between the OOAm hypothesis and hypotheses that place human origins in other continents. It counts as an interesting piece of evidence regarding human presence in the Americas, but does not speak to the validity of OOAm, because it tells us nothing about how these humans got to be in the Americas.

It is worth noting that although Nichols (1990) does indeed argue for an earlier human presence in the Americas than do hypotheses based on physical remains, the entire point of the article is to develop a estimate for the date of human colonization of the Americas, based on linguistic evidence. Dziebel takes the early date for human presence in the Americas presented in the paper as support for the OOAm hypothesis, but discards the fact that this date is given in the context of a model for colonization of the Americas from the Old World.

Let us now take up Dziebel’s second point, which concerns the relative linguistic diversity of the Americas and Africa. Nichols (1990) observes that if one looks at the density of linguistic stocks globally, certain areas, such as New Guinea and South America, show a higher density that other areas, such as Europe. And, as Dziebel correctly notes, the density of the Americas as whole is higher than that of Africa. But, does this fact count as evidence either for or against OOAm? No, not at all.

Dziebel interest in the relative linguistic diversity of the Americas and of Africa lies in the supposed ability of linguistic diversity to predict the age of populations:

To summarize, linguistic diversity is a good and straightforward predictor of a population’s age if geography is factored in and if it’s checked against the mtDNA and Y-chromosome picture.

While it is certainly true that, all other things being equal, linguistic diversity in a region increases over time, it does not follow that linguistic diversity is a straightforward indicator of the age of that area’s population. The confounding factor is large-scale language shift. As Nichols argues, there is good reason to believe that in Europe, for example, Indo-European languages replaced pre-Indo-European languages on a massive scale, radically reducing the linguistic diversity of the region.

Of course, Dziebel also mentions the “mtDNA and Y-chromosome picture” — but it’s not clear to me how this is relevant to the utility of using linguistic diversity to estimate the age of a population, unless his following comment gives us a clue:

Linguistic diversity steadily increases with time, unless this process is checked by geography and reversed by population replacements.

So here it appears that Dziebel makes use of the concept of ‘population replacement’ to account for interruptions in the steady growth of linguist diverstiy. But of course, language shift need not co-occur with population replacement, entirely disrupting the tidy correspondence between linguistic diversity and the age of populations. In Europe, for example, Nichols argues that Indo-European *languages* replaced pre-Indo-European ones, not that *populations* were replaced. The result was a loss of linguistic diversity. And as the following comment shows, Dziebel seems perfectly aware of this fact:

Translated into the levels of linguistic diversity, Europe experienced periods of language replacement (now it’s dominated by Indo-European languages) but all these replacements originated from the same genetic pool.

But then he concludes:

However the factors of geography and population replacement are subordinate to the factor of spontaneous differentiation because differentiation occurs all the time and everywhere, while geographical constraints and population replacements are accidental events.

What Dziebel seems to be arguing here is that even though we know that language shift occurs — and on vast scales, as in Europe and Africa — at the end of the day, linguistic diversity is still a reliable measure of a population’s age. But this is clearly false — or maybe I am misunderstanding his point. The fact that large-scale language shift occurs, without necessarily significant changes in the *biological* population, means that linguistic diversity is good as a measure of the amount of time that has transpired *subsequent to* such large scale linguistic shifts. These shifts largely erase the linguistic history of an area, screening off the population’s age prior to that point from measures based on linguistic diversity.

The fact that such large scale shifts appear to have occurred in Africa and Europe means that measures of linguistic diversity simply cannot tell us very much about the ultimate ages of those populations. Consequently, the fact that the Americas display greater linguistic diversity than Africa tells us nothing about the relative ages of the populations of the two regions. The linguistic diversity evidence that Dziebel cites simply does not bear on the validity of OOAm.

Apart from the linguistic diversity evidence just discussed, Dziebel also cites typological evidence:

The distribution of grammatical features (such as head-marking vs. dependent-marking, numeral classifiers, etc.) again shows a cline from America and Australasia to Africa and Europe, and Nichols’s argued that our perspective on an early human language comes from America and Australasia and not Africa and Europe.

It is certainly true that Nichols (1990) observes certain typological features appear to cluster in certain geographical areas, and that intermediate areas show intermediate values for the parameters in question. Thus, as extremes, South America shows a very high proportion of head-marking languages, while Europe and Africa show a very high proportion of dependent-marking languages. Intermediate areas, such as Australasia, tend to show either mixed-marking or double-marking. However, the fact that one can identify typological parameters that exhibit a cline of values between the Americas, on the one hand, and Europe and Africa, on the other, tells us little about the locus of modern human origins. By themselves, these linguistic facts are consistent with both OOAm and OOAf scenarios. They simply do not speak to validity of one hypothesis over the other.

Dziebel also says, however, that “Nichols’s argued that our perspective on an early human language comes from America and Australasia and not Africa and Europe.” Well, if she does so in Nichols (1990), I can’t find it. The closest argument I can find in Nichols (1990) to the one that Dziebel attributes to her is an observation about the relationship between colonization and the preservation of linguistic features. To summarize, Nichols observes that when new areas are colonized, it is not unusual for linguistic features to survive in the colonized area that are subsequently lost in the areas from which the linguistic stocks originally spread. Note, of course, that the languages in the colonized area continue to change, as do all human languages, so it is misleading to characterize them as somehow reflecting “early human languages”. Rather, the languages in questions simply preserve some features that were present at the time of colonization, and which tend to get lost in the original area due to language shift. Note, btw, that *were* it possible to show that American languages retain certain features subsequently lost in other parts of the world, this would actually serve as evidence, following Nichols’ arguments, for the Americas having been colonized from the Old World, rather than the reverse, as Dziebel proposes.

Thus far, then, I can find no evidence in Nichols (1990) that supports the OOAm hypothesis. I now wish to briefly review evidence given in the paper that argues against the OOAm hypothesis.

First, linguistic diversity in the Americas tends to increase the further south one goes. Modulo issues of language shift, touched on above, this fact suggests that the older American populations are found in the south, and successively more recent populations are found in Meso-America and North America. These facts are easy to reconcile with a scenario in which populations entered the American in the north in stages, with subsequent populations pushing prior ones towards the south. It is not clear how these linguistic diversity facts fit with an OOAm scenario.

Second, Nichols argues that linguistic diversity is, in general, higher in areas that have been colonized than the centers from which colonization occurred (a point to which I alluded above). Nichols argues (p. 487) that this is due to the fact that centers are loci of large scale economies, which result in linguistic spreads that reduce linguistic diversity. The greater linguistic diversity of the Americas is, by this reasoning, supportive of the Americas being a colonized region, and not the OOAm hypothesis.

To summarize, Dziebel cited Nichols (1990) as a source of evidence and arguments that support the OOAm hypothesis. In particular, Dziebel cites linguistic evidence from this work for the antiquity of human settlement in the Americas and for the existence of a typological cline linking the Old World and New. However, neither piece of evidence supports an OOAm scenario over a OOAf scenario (or vice versa). However, other evidence and arguments presented in Nichols (1990) casts doubt on an OOAm scenario. In particular, the evidence regarding linguistic diversity within the Americas is consistent with a process of colonization of the New Word by multiple migrations from the north, but is not easy to reconcile with a an OOAm scenario. Additionally, Nichols makes arguments regarding the effects of colonization on linguistic diversity which are consistent with the Americas being the site of colonization, but not with the Americas being the point from which the Old World was colonized.

Regardless of the ultimate validity of the OOAm hypothesis, then, the linguistic arguments Dziebel presents in its favor are unconvincing to me. I wish to emphasize that I am restricting my attention to the linguistic arguments, and it is possible that the genetic arguments or those based on kinship terminology provide much better evidence for OOAm. At this point, however, I am led to conclude that the linguistic evidence that Dziebel has presented so far in favor of OOAm is weak.

14 Responses to “Evaluating the linguistic evidence for an Out of America hypothesis”

This is a premature assessment. I’d like you to read Nichols 1992 and Dziebel 2007. “Nichols’s argued that our perspective on an early human language comes from America and Australasia and not Africa and Europe” refers to Nichols 1992. The exact quote is in Dziebel 2007.

Nichols has no affinity to the OOAm hypothesis. OOAm has been independently developed by me, on the basis of a global analysis of kinship systems and terminologies and the reinterpretation of population genetics, from 1994, and by Alvah Hicks (www.humanoriginsolved.com) on the basis of archaeology and the reinterpretation of genetic data from the late 1980s. I know Nichols personally (Stanford and Berkeley are close by), but she has nothing to do with OOAm.

In Nichols 1990, 1992 she was working under the traditional assumption that New World (America and Australasia in her usage) was peopled from the Old World (Asia, Africa and Europe). That’s why she interpreted high levels of linguistic diversity as indicator of a refugium, and low levels of linguistic diversity as indicator of a spread zone with language replacement. Under the pressure from kinship terminological evidence and the “noise” in the current mtDNA phylogenies, I allowed myself the liberty to remove the assumption that the New World was peopled from the Old World, and allow an infinitely possible number of back migrations including the original OOAm migration to colonize the Old World.

If my opinion, if linguistic diversity levels are taken at face value, then the most parsimonious explanation is the accrual of stock diversity in the homeland and the lack of sufficient time for this accrual in the colonized areas. Language replacements and language loss can occur with equal probability on all continents (agricultural and other expansions are attested in both America and Europe and Africa), while diversity levels are clearly different between Europe/Africa and America/Australasia. Hence, these two factors are of unequal value, and the latter supercedes the former, unless specifically proven otherwise.

Nichols was criticized by Nettle and Dixon, but I think their arguments are invalid because they are based on an ad hoc assumption of who came from where. Nettle shot himself in the foot by admitting that American Indian linguistic diversity is compatible with any time depth, all the way to 100,000 YBP. More about it on anthropology.net.

Another factor is geography: grammatical features studied by Nichols again show unequal and non-random distribution, as you correctly deduced from my anthropology.net posts. Interestingly enough, the geographic range of head-marking (assuming it’s ancestral) is wider than dependent-marking (assuming it’s derived). HM languages are found all over Asia, Australasia and America, while dependent marking languages are largely confined to Africa and Europe. This indicates the transition from HM to DM going into Africa and Europe. I need to double-check it again, though. (mtDNA shows a similar pattern with all African lineages being African-specific and 90% of European lineages being Europe-specific, while Asian and American lineages are found globally.)

While your general caveat that linguistic diversity doesn’t directly resolve a continental population’s age is valid, the same concerns population genetics where America is interpreted as a recently colonized continent because it’s less diverse than others, while Africa harbors the greatest diversity. In reality, genetic diversity is a function of population size. American Indians are less diverse simply because their long-term population size was smaller than the Old World population size. In addition, African genetic lineages are not found outside of Africa, which contradicts the hypothesis of population replacement outside of Africa by Africans.

OOAm is based on the alignment of interdisciplinary data. I understand all the diffuculties with OOAm and with OOAf. I juxtapose them as two theoretically possible variants of a single-origin hypothesis to be able to test one against the other. Since both genetically and linguistically Africans and Amerindians are the exact polar opposites of each other, they are specific enough to warrant such a test and make OOAm or OOAf falsifiable.

Thank you for your lengthy reply. In this reply I want to focus specifically on the substantive empirical and analytical points you raise. (Readers interested in situating Dziebel’s comment in the ongoing discussion may wish to visit the comment thread on anthropology.net, where he has also posted his reply to me.)

In regards to my observation that Nichols (1990) argues that colonized areas exhibit greater linguistic diversity that the areas from which the colonizations originated, you wrote:

In Nichols 1990, 1992 she was working under the traditional assumption that New World (America and Australasia in her usage) was peopled from the Old World (Asia, Africa and Europe). That’s why she interpreted high levels of linguistic diversity as indicator of a refugium, and low levels of linguistic diversity as indicator of a spread zone with language replacement.

It is certainly true that Nichols (1990) assumes colonization of the New World from the Old World, but I disagree that this is *why* she concludes that colonized areas exhibit relatively higher levels of linguistic diversity. In her discussion of this question (pp. 487-488), the case studies she cites concern the linguistic diversity found on obviously colonized islands, — specifically Bougainville, New Britain, and Sakhalin — and she doesn’t use the New World *at all* to construct her generalization. It seems to me that she is actually being very careful to avoid circularity here. Can you point to any evidence that indicates that her generalization regarding the relationship between colonization and linguistic diversity depends in any significant way on assumptions about the peopling of the Americas?

The *empirical* fact is that the relative linguistic diversity of the New World in comparison to the Old World patterns with the linguistic diversity of colonized islands relative to the mainlands from which they were colonized. That observation is quite independent of OOAm or any competing explanation. The simplest (though not necessarily correct) explanation for this fact is that the Americas served as a site for colonization, not as the source of colonization. To be sure, this is just *one* piece of evidence, and it is far from conclusive, but that is the way this one piece of evidence points.

The next point you raise responds to my criticism of the straightforward use of linguistic diversity to estimate the ages of populations:

If my opinion, if linguistic diversity levels are taken at face value, then the most parsimonious explanation is the accrual of stock diversity in the homeland and the lack of sufficient time for this accrual in the colonized areas. Language replacements and language loss can occur with equal probability on all continents (agricultural and other expansions are attested in both America and Europe and Africa), while diversity levels are clearly different between Europe/Africa and America/Australasia. Hence, these two factors are of unequal value, and the latter supercedes the former, unless specifically proven otherwise.

I’m surprised you make this argument, since Nichols (1990) addresses these issues in detail, and reaches quite different conclusions. In particular, the following key point in your argument seems to be incorrect: “Language replacements and language loss can occur with equal probability on all continents (agricultural and other expansions are attested in both America and Europe and Africa)…”

I don’t think issues of ‘probability’ are particularly relevant here, since there is evidence of major linguistic spreads in Europe and Africa but *not* in the Americas. As Nichols (1990) argues at length, the Indo-European and Afro-Asiatic stocks show a very high number of surviving families in comparison to other stocks (pp. 489-490), which is indicative of rapid radiation, i.e. linguistic spread. Nichols relates this directly to the development of ‘large-scale economies’ in Europe and Africa. Nichols shows that in the specific case of the ancient Near East, the rise of large scale agricultural societies was associated with a significant drop in linguistic diversity (p. 486). In the Americas, in contrast, we find no evidence of large scale spreads that radically altered the diversity of the region.

Continuing with your previous comment, then:

Language replacements and language loss can occur with equal probability on all continents (agricultural and other expansions are attested in both America and Europe and Africa), while diversity levels are clearly different between Europe/Africa and America/Australasia. Hence, these two factors are of unequal value, and the latter supercedes the former, unless specifically proven otherwise.

Well, it seems to me that it *has* been proven otherwise — Europe and Africa experienced linguistic spreads that significantly reduced their linguistic diversity, whereas the Americas did not. As a result, measures of relative linguistic diversity do not tell us anything about the relative ages of the populations in the these regions.

The final linguistic empirical point you raise is relates to large-scale distributions of head-marking versus dependent-marking languages:

Another factor is geography: grammatical features studied by Nichols again show unequal and non-random distribution, as you correctly deduced from my anthropology.net posts. Interestingly enough, the geographic range of head-marking (assuming it’s ancestral) is wider than dependent-marking (assuming it’s derived). HM languages are found all over Asia, Australasia and America, while dependent marking languages are largely confined to Africa and Europe. This indicates the transition from HM to DM going into Africa and Europe.

As I attempted to articulate in my original post, it seems to me that the distribution of grammatical characteristics, such as head-marking versus dependent-marking, are incapable of distinguishing between OOAm and OOAf. You claim that: “This indicates the transition from HM to DM going into Africa and Europe.” But why couldn’t this distribution be used to make the exact opposite argument: “This indicates a transition from DM to HM going into the New World?” I have a hard time seeing how these distributional facts can distinguish between the two theories.

I wish to emphasize again that I am not seeking to argue against OOAm as such — I am simply interesting in what the linguistic evidence, which I do not expect to be at all conclusive, tells us.

I would like to add that we cannot really compare the linguistic diversity of America with that of Europe, not just because of the specifics of Indo-European deletion of whatever was before (some of which is roughly known and seems quite diverse) but specially because the level of linguistic studies re. Europe is about one century ahead of that of American native languages. Would we be re. Europe at the stage of America, we would probably not recognize any uncontroversial similarity between Indo-European languages, much less NW and NE Caucasian or Uralic languages. We would have (and we used to have) dozens of families, whose interconnections would be obscure and controversial.

Another factor is size: Europe is 10 million square kilometers, North America alone is 2.5 times that size (all America would be like 4.25 times Europe). Certainly distances should favor diversity somewhat, as it doesn’t make much sense to speak a different language in each village or valley. Therefore, everything else being equal, North America should have a diversity 2.5 times that of Europe.

We can see that only with the most conservative classification we get more diversity/area in Native North America than in Europe, even if we would count only living families. We can easily assume that the pre-Chalcolithic (pre-IE) diversity in Europe was much bigger than just 12 families, specially because most of the documented families come from two small subregions: Iberia and the northern Caucasus. It’s easy to imagine that regions like Britain, France, Scandinavia, Italy, etc. had similar high diversity prior to IE advance.

But even when we only consider what we can document, we still find that the alleged much higher American diversity is not clear at all. At least not for the North American case. We don’t need to accept Greenberg’s model, Voeglin’s also give half the diversity/area documented for Europe.

The very assumption of higher linguistic diversity in America may perfectly be just a fallacy born out of ignorance and/or convenience.

Yes, I think you have a good point here. The comparative/historical linguistics of South America is is especially embryonic. There are a lot of unresolved classificatory issues that bear on gross linguistic stock counts, and I agree that a century from now, our understanding of the linguistic diversity of the area will be different in important ways.

Now, if one really wanted to defend NIchols´stock counts as solid, one could point to her actual definitions of the terms ‘stock’ and ‘family’, which are distinguished mainly in terms of degree of obviousness of connection. (I’m now in the jungle, so I’m doing this completely from memory.) One could then argue that discovery of new genetic relationships among these languages is unlikely to affect the counts of stocks, based on the ‘degree of obviousness’ definition. I don’t think I would want to defend this position very vigorously, but it may be a way to counter the problems you raise.

One could then argue that discovery of new genetic relationships among these languages is unlikely to affect the counts of stocks, based on the ‘degree of obviousness’ definition.

I did not count stocks, as per Nichols, because I am not really into Native American linguistics and found too much work to find out the total number of stocks+isolates without self-teaching myself a lot more. I went to the easy counts, as they were enough to make my point clear.

But, if you wish, as you are surely much more familiar with the issue, you can do that count yourself. My impression is that it would give a ratio close to that using Voeglin’s scheme, probably somewhat more diverse but quite lower than with the ultraconservative scheme in any case.

The “conservative” classification of North American Indian languages is the only one that exists and that ensures that we can speak the same methodological language, no matter where we work – in North America or in Europe. The Voegelins’ classification counted phyla, not stocks, and phyla are hypothetical groupings, not endorsed by traditional methods. The same method, if applied to Europe, would result in only 4 phyla – Eurasiatic/Nostratic, Basque and North Caucasian. Greenberg didn’t replace the “conservative” classification with his own, but only added a new level of visibility to the linguistic material, which linguists generally believe is illusional. Even your calculation, which I think is interesting, makes North America twice or four times as diverse as Europe.

Lev,

Thanks for your jungle thoughts. A much needed perspective.

Nichols worked under the assumption that America was peopled just because everybody else always did. (Robert Austerlitz in “Language Family Density in North America and Eurasia”, p. 1 stated this assumption clearly, and Nichols used his work as a jumping board for Nichols 1990.)

Unlike me, Nichols’s not interested in challenging this assumption. Her point was that if traditional historical linguistics is asked about the timing of the peopling of the Americas, it would vote for an “early entry.” Greenberg made an attempt to reconcile American Indian linguistic diversity with the Clovis-I timeline, so in response to his sloppy new classification Nichols provided an opinion more in line with what specialists in American Indian languages would be comfortable with and with the comparativist methodology of historical linguistics. Her work in “population linguistics” isn’t without its critics (such as Lyle Campbell, who sent me some very helpful comments a couple of years ago), but nobody denies the fact that linguistics, if treated diachronically, provides evidence for an “early entry” into the Americas. But this “early entry” may mean “authochthonous isolate” if this hypothesis is entertained at all.

I am not understanding your reading of Nichols regarding “language spread” in the Old World. Yes, IE, Afroasiatic and Niger-Congo have a lot of families and a lot of speakers subsumed under the same category of “stock.” (Sino-Tibetan and Austronesian, by the way, are comparable to Niger-Congo in the number of Nichols’s “families” and it’s outside of Europe and Africa, so we can’t say that these massive stocks occur only in Africa and Europe.) But Nichols never wrote that we can be certain that all these stocks have absorbed hundreds of substratum languages. (Neither can we say that the reason why these stocks are so rich in families and languages is because all those families and languages ARE in fact an absorbed substratum.) This would be the only way one could falsify the wide discrepancy between New World and Old World linguistic diversity. And this finding, improbable as it is, would only equalize the New World and the Old World. Europe and Africa are a neutral “spread zone” in Nichols’s terms, and a “zone into which languages spread”, in my theory. I specify Nichols’s arguments and remove the assumption of which of the two worlds is “new.”

As of now, we have agricultural expansions, which are known for their ability to eliminate earlier hunter-gatherer diversity, in both the Old World and the New World. In the Old World, these expansions were associated with a larger population size, and this explains the number of families within a stock but also checks for time depth (regardless of the number of the families within a stock, it’s the stock level that is indicative of a considerable time depth).

Now, the great population size in the Old World translates into the high molecular diversity (note that in Africa allele diversity is higher among agriculturalists such as Bantu than among hunter-gatherers such as Khoisans. We can tentatively “date” the radical increase in molecular diversity in the Old World vs. the New World by the time of the expansion of Sino-Tibetan, Austronesian, Afroasiatic, Niger-Congo and Indo-European, which is probably within the last 10,000 years. Prior to the late Holocene, the levels of genetic diversity in the Old World were comparable to those in the New World.

Hence, we have a good concordance between levels of genetic and linguistic diversity and a good test for the “validity” of the linguistic diversity in the New World for any time estimates. To sum up, Nichols’s “language spread” has nothing to do with the number of languages being absorbed or with their stock affiliation. In North America, one extinct language, Beothuk, was lost as a result of a joint effort between European colonists and some Algonquian-speakers. But from the surviving vocabulary we can say that Beothuk was possibly of Algonquian affiliation, but we would never know this for sure. Low population size and density, in turn, can result in random loss of languages through physical extermination by neighbors or through encounter with an adverse natural environment. In North America, in the 18-19th centuries, California and Texas suffered from such a rapid “industrial” replacement that we can’t even say how many languages and of what stock-affiliation ended up lost.

It’s certainly true that we can’t simply interpret linguistic diversity only through a temporal prism. Places like the Balkans, where three branches of the IE family are attested, those being Albanian, Slavic and Greek, illustrate the fact that high diversity may be of secondary nature. The coming-together of several families may create a linguistic picture also consistent with what we would expect from a homeland (such as the Northwest Coast/Alaska for Na-Dene, where Eyak, Tlingit and Athabascan are found). There’re two ways to test this on a continental scale: first, to study the grammatical patterns between America and the Old World; second, to look if genetics can support the origin of American Indian populations from 150-200 (the number of stocks in America) different migrations; third, to look at kinship systems as they are embedded in language but also translate into demography and population genetics.

There’s no genetic study to date that suggested that America was peopled as a result of a hundred different migrations. This would bring into America all the copies of Asian-pervasive mtDNA “M” markers, while in reality American Indians are linked to Asia only through “rare” Asian markers. The majority of genetic studies concur that Native Americans were founded by one migration.

As for the first, Nichols found that grammatically American Indian languages belong broadly with Australasia, and not narrowly with Siberia or Northeast Asia. Then, she interpreted the distribution of grammatical characters historically (HM > DM, but not the other way around). Since American linguistics is heavily structural and synchronic, she used the Soviet linguistic tradition for the methodology of interpreting grammar in evolutionary terms. (She is a Slavist in addition to everthing else, so she was familiar with that literature.) Specifically, she relied on the work of Klimov, whose books I’d read in Russian even before encountering Nichols. He divided all languages into active, ergative and nominative, and suggested that active languages represent the earliest syntactic type. Nichols skillfully and creatively modified his results to make them more palatable to the American audience. Plus added her own database and analytical precision.

The basic opposition between HM and DM carries with it a whole host of asscoiated grammatical features such as inclusive/exclusive, presence/absence of “inalienable possession,” etc., which, as the recent WALS can illustrate, demonstrate the contrasting pattern of New World vs. Old World very clearly. Mind you that genetics identified exactly the same contrast.

What I found in kinship systems is that the grammatical patterns are related to kinship terminological patterns (e.g., kin terms are likely to be isolated into the special category of inalienably possessed items in the New World but not in the Old World, where this opposition is rarely expressed on the surface; New World languages have the “vocative vs. referential” distinction, which is related to inalienability, for vocative kinship forms usually drop the marker of possession, while Old World languages don’t, etc.). Then all these features of “kinship grammar” further correlate with kinship semantics, and here we find more and more oppositions between the New World and the Old World. Kinship studies have worked with diachronic models from their very inception, and the same contrast between the Old World and the New World as Nichols identified in grammar, Lewis Morgan had identified in kinship systems 150 years ago.

All these considerations reinforce Nichols’s findings as well as my more far-reaching OOAm idea. In and of itself, of course, language can offer only suggestive hints.

Thanks for your comments. I´m afraid I don´t have the time to respond properly at this point — I’m just passing through Iquitos briefly on my way between fieldsites. I’ll be sure to respond at length once I’m back in long-term email contact.

The same way that the linguistic diversity of the Americas is obviously overestimated, that of Africa may be underestimated — I just say Nilo-Saharan. More importantly, Africa has had the Bantu expansion steamrollering over who knows what.

the same concerns population genetics where America is interpreted as a recently colonized continent because it’s less diverse than others, while Africa harbors the greatest diversity. In reality, genetic diversity is a function of population size.

As well as of time — see founder effect.

American Indians are less diverse simply because their long-term population size was smaller than the Old World population size.

Does that include Africa? I’d like to see numbers on that.

In addition, African genetic lineages are not found outside of Africa, which contradicts the hypothesis of population replacement outside of Africa by Africans.

This wouldn’t pass peer-review. The fact that only one of the many African lineages, one that occurs in northeastern Africa, is found in the rest of the world, and that nothing else is found there, fits the hypothesis that only people from the northeastern corner of Africa got out of Africa. Principle of Parsimony sez “we have a winner”.

The linguistic diversity in the Americas is “obviously” overestimated? I would need something more than “obvious” to even begin thinking about it. Something of the sort of “American Indian languages: The historical linguistics of Native America” or “The languages of Native America: Historical and comparative assessment.”
But no matter how hard we try to diminish Amerindian linguistic diversity and boost up African linguistic diversity, they are just no comparison. There just more people in Africa, that’s all there’s to it. America, on the other hand, shows great time depth. The Bantu expansion proves nothing until we find substratum evidence in these languages, which we haven’t so far.

How dooes “time” relate to the “founder effect”?

America being less diverse than African genetically is the indicator that effective population size has been smaller in the Americas than in Africa. This is elementary population genetics. You can interpret it historically by assuming that the reduction in effective population size in the Americas was the result of a small group of hunters budding off from a larger population in East Asia and colonizing a new continent, but an opposite scenario is equally possible: America retained the original small effective population size, while the Old World was colonized through population expansion which means a significant increase in the effective population population size outside the Americas. The first scenario has been belabored ad infinitum without proof. The latter one is fresh and explains linguistic diversity very well.

Which northeast African lineages left Africa? I am not aware of a single one. If you mean mtDNA M1, then it’s proven to have been the result of a back migration to Africa. If you look at Y chromosome, African-specific lineages A and B are decisively not found outside of Africa. They are restricted to Khoisan and Pygmies. YAP+ lineages are controversial, but with new findings in India and Andaman Islands they are likely to indicate a migration into Africa.

I appreciate your patience in waiting for a response. Let me first observe that we both seem to find Nichols argument for a comparatively early human presence in the Americas to be plausible. I think we would also both agree that Nichols arguments regarding this early date are incapable of distinguishing between early settlement and authochthonous origin hypotheses. Nichols’ methods – and really, any accepted historical linguistic methods – simply cannot reach back far enough to distinguish the two hypotheses. So I see Nichols’ dates as being more friendly to an OOAm hypothesis that other accounts, but they still seem very far from being compelling scientific evidence for an OOAm hypothesis. Restricting our attention to this issue of dating, does that seem like a fair assessment to you?

Let me now turn to the issue of the distribution of head-marking (HM) versus dependent-marking (DM) languages as support for an OOAm hypothesis. As you note, a number of grammatical features tend to cluster with HM or DM status. You then observed that New World languages tend to be HM, and that Old World languages tend to be DM. So far so good — but I still don’t see how this constitutes compelling evidence for an OOAm hypothesis, even if one accepts irreversible HM>DM historical development (about which, I must say, I am skeptical). It seems to me that the empirical facts on which we agree cannot usefully distinguish between OOAm and alternate theories.

For the sake of concreteness, let’s examine how both OOAm and OOAf are consistent with the distributional facts noted above. Under an OOAm scenario, humans originate in the Americas, speaking HM languages. They then spread to Siberia, and radiate out to fill up the rest of the world. The languages of those emigrated out of the Americas then develop into DM languages in such a way as to result in the cline we see between the HM-heavy Americas and the DM-heavy Old World. Well and good.

However, one can tell exactly the opposite story just as well, it seems to me. Humans originate in Africa, speaking HM languages (under the hypothesis). They radiate out from Africa, eventually populating the New World. In the Old World, the languages develop into DM languages, while in the Americas, they remain HM languages, with the in-between areas forming a cline between the two extremes.

It seems to me that both scenarios sketched out here fit the basic linguistic empirical facts equally well, even under the HM>DM restriction. Is there a flaw in my argument here? Recall, btw, that Nichols argues that colonized areas tend to preserve linguistic traits lost in those areas from which people emigrate, so the HM>DM stipulation lends greater support to a non-American origin for humans that the opposite. Note, however, that I remain skeptical of the HM>DM restriction.

Now, you also raise a number of non-linguistic arguments to support an OOAm account, and I will repeat that I do not feel qualified to evaluate them. They may well be able to resolve matters where the linguistic ones cannot, but I remain neutral on this point. Once again, however, I have to say that I just don’t see that the linguistic evidence lends much support to either OOAm hypotheses or to their rivals. It seems to me that historical linguistic methods are simply inadequate to say much about linguistic diversification and change at the time depths necessary to distinguish between the hypotheses in question.

Now, let me respond to one of your comments, which I have compacted somewhat to capture the essence of your point (as I understand it):

I am not understanding your reading of Nichols regarding “language spread” in the Old World. Yes, IE, Afroasiatic and Niger-Congo have a lot of families and a lot of speakers subsumed under the same category of “stock.” […] But Nichols never wrote that we can be certain that all these stocks have absorbed hundreds of substratum languages. […] This would be the only way one could falsify the wide discrepancy between New World and Old World linguistic diversity. And this finding, improbable as it is, would only equalize the New World and the Old World. Europe and Africa are a neutral “spread zone” in Nichols’s terms, and a “zone into which languages spread”, in my theory.

Well, what Nichols was arguing is that the ‘bushiness’ of IE points to a relatively recent (on the scale of total human history) spread. That is, the language-to-family and the family-to-stock ratios suggest that the stock has undergone a large spread. Given the fact that we have evidence of a linguistic spread (and I think we are in agreement here), and given the archeological record of the Old World, which points to human habitation that significantly predates the spread of IE, I believe we have to conclude that the extant IE languages displaced previously existing languages. Unless these languages were members of other (unknown) branches of IE — which I don’t think anyone believes — the effect of the IE spread would have been to lower the linguistic diversity of the currently IE-dominated areas.

In the Americas, however, we do not have evidence of spreads of the same scale, which means that comparing the age of populations in the Americas and the Old World using linguistic diversity as an index is simply not possible. The (apparently) different linguistic histories of the two regions — in particular, the different impact of linguistic spreads in the two different regions — means that comparing linguistic diversity in the two regions tells us very little about the relative ages of the populations.

This arguments seems to me to be fairly straightforward, so I’d be grateful if you would explain why you believe linguistic spreads in the Old World do not pose a problem for using linguistic diversity as a measure of population age.

Thanks for your detailed responses, and once again, for your patience in waiting for my response.

Thanks for finding some time to continue this conversation that I find useful. Your style of argumentation reminds me of my friend Lev Blumenfeld who now teaches linguistics at Carleton.

Your standards of proof apply to facts, not to theories. Neither archaeology, not population genetics – the two disciplines who largely control our understanding of human prehistory – will be able to satisfy them. Human origins research is not an experimental science, and the task of OOAm is to show precisely what you’re trying to impute it with: the directionality of global migrations as inferred from the currently available archaeological, genetic and linguistic data can be reversed without any loss of content. Ultimately it deppends on the “population scenario of how things happened in reality” but then this is exactly what we’re trying to figure out. The value of OOAm is not only that it creates a consistent theory of how humans dispersed without giving genetics or archaeology an apriori upperhand but that it presents our human origins reserach as a paradox stemming from the nature of our data – it’s indirect.

Another question is how we build an argument on linguistic grounds: do we resort to archaeology to fill in a gap when we need to prove something (like you do with the IE dispersal), or we’re staying with linguistics and reporting only on what we observe from linguistic data. Linguistic diversity in the Americas stands out as very extensive for a recent population. It’s consistent with linguistic diversity in Oceania, and this is precisely where we find correspondences in grammatical features as well. Stock diversity in Africa and Europe is low, and there’s no way we can prove that it used to be of Ameirindian-Oceanic magnitude 10,000 years ago. This is a special argument that requires special proof, and you haven’t presented it.

I hope you’re still interested in this topic. If you are, here’s a relevant paper by Roger Blench in which the question of American Indian linguistic diversity is discussed again. Needless to say, he doesn’t venture into hypothesizing an out-of-America scenario but seems to uphold all the points about Amerindian antiquity raised originally by Nichols and then by me in “The Genius of Kinship” and on anthropology.net.

I noticed that you said all human languages change, there is however one that cant be changed as it (though neglect and ignorance have degraded it a bit) appears to be based on a tri-valent logic system incorporating an algebraic algorithim in order to formulate expressions and meanings many of which cannot be translated accurately to other languages, though expressions in all other languages appear possible in this one. And it is all done using only a base word and suffixes which will give it meaning. Of course I speak of aymara which is not an amazonian language as your blog appears to be focused on it is nonetheless a language. A paper was written on this in the 80s but i struggle to find any new information, it is believed that this language may have been engineered by some group of people who took into consideration at every event whether something were to occur, not to occur, or uncertain. Only it and another language, quechua,(perhaps other andean languages as well) follow this logic. It is my own belief that each was engineered seperately at different times and so could not possibly appear to be related since they were purposefully created to appear different, the reason for this is mystery, however it is believed the original inca was an aymara speaker and only shortly before their expansion was quechua adopted. Both languages are much older than this however. Perhaps, if they really are both engineered, they actually are derived from the same cultural source and there is no proto-quechua or proto-aymara. Anyways just interesting things to think about.

by mentioning the inca as an aymara speaker i meant to infer that perhaps the two groups were in conflict but originated from the same source, or at least their languages originated from the same source of logic, may be that the quechua split off from the aymara. and the inca was simply an aymara that switched over. if you would like to read the paper here is a link.

i would like to know what an actual linguist would think as i am not even studying languages rather systems engineering and since it concerns my people and the idea of an engineered language one in tri-valent logic nonetheless intrigues me.